Vent for exhaust system

ABSTRACT

A vent for venting of exhaust from a building comprising at least one inlet for receiving the exhaust from the building into the vent; at least one valve for assisting in maintaining the unidirectional movement of exhaust from inside to outside the building; and an outlet for allowing the release of the exhaust from the vent; wherein the inlet meets the vent at a forward angle such that the exhaust flows towards the outlet and acts to reduce friction of the exhaust against the vent.

FIELD OF INVENTION

The present invention relates to a system and apparatus for an improved vent for building exhaust.

BACKGROUND ART

In order to provide a vent between the interior and exterior of a building, the building industry has been using standard mushroom vents on building roofs for decades. These roof vents were designed for standard ceiling fans commonly used in bathroom, laundries, toilets and kitchens.

The performance of these vents has been a grey area in the industry for some time, as the outlet in the vent was not designed for the high volume of air produced by the latest exhaust systems available today. There are problems with back pressure caused by the restriction of the mushroom caps, thereby resulting in the exhaust system becoming noisy, motor vibration and excessive wear due to the strain of the exhaust motor trying to push the air through a restricted vent.

Further, mushroom vents are cheaply manufactured, look undesirable and often leak due to ineffective installation. As exhaust blows directly down onto the roof from the mushroom cap, staining of the roof is caused, especially from kitchen rangehood exhaust, where odours, cooking vapours and fine molecules of fat are exhausted.

The present invention attempts to overcome at least in part the aforementioned disadvantages of previous roof venting for exhaust.

SUMMARY OF INVENTION

In accordance with one aspect of the present invention there is provided a vent for venting of exhaust from a building comprising:

at least one inlet for receiving the exhaust from the building into the vent;

at least one valve for assisting in maintaining the unidirectional movement of exhaust from inside to outside the building; and

an outlet for allowing the release of the exhaust from the vent;

wherein the inlet meets the vent at a forward angle such that the exhaust flows towards the outlet and acts to reduce friction of the exhaust against the vent.

The angle at which the inlet meets the vent may be between about 20 and 50 degrees.

The angle at which the inlet meets the vent may be about 35 degrees.

An angled spigot may be connected to an entry to the inlet.

A default closed position oft e valve ay be maintained through the force of gravity.

The vent may comprise a plurality of inlets and a divider disposed between the inlets for providing a physical barrier between respective inlets.

A rear wall of the vent may be angled outwardly from a base to a top of the vent.

The outlet may be covered with a screen for allowing exhaust to be expelled from the vent while minimising the ingress of foreign articles to the vent.

The screen may be constructed of cinder mesh for the prevention of ingress of embers in a fire situation.

The vent may further comprise insulation isolating the screen from other material of the vent at points of contact between the two.

The vent may further comprise fingers for complementary attachment of the vent to a corrugated building surface.

The vent may further comprise a malleable skirt for moulding over a surface upon which the vent is mounted.

A shell of the vent may be formed of a box and a shroud.

The box and the shroud may each be formed of a solitary piece punched from sheet material, then folded and fixed into its finished shape.

In accordance with a second aspect of the present invention there is provided a method of venting exhaust from a building comprising the use of a vent apparatus as described above.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is an upper perspective view of an improved roof vent with two inlets 18 in accordance with a first embodiment of the present invention.

FIG. 2 is a lower perspective view of the roof vent of FIG. 1;

FIG. 3 is a side section view of an improved roof vent with one inlet 18 in accordance with a first embodiment of the present invention;

FIG. 4 is a front section view of the roof vent of FIG. 1; and

FIG. 5 is a top section view of the roof vent of FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the Figures, there is shown an apparatus for improved roof venting for exhaust, generally indicated by reference numeral 10. As best seen in FIG. 1, the exhaust roof vent 10 comprises a shroud 12 and box 14 forming a shell of the vent 10. It is preferred that the shroud 12 and box 14 are constructed from COLORBOND® steel to complement steel-roofed buildings, for example, and from 0.55 mm galvanised tin to complement tiled roofs or walls of other materials upon which the vent 10 is mounted. Each of the shroud 12 and box 14 are preferably formed of a solitary piece punched from sheet material, then folded and fixed into its finished shape.

The shroud 12 comprises fingers 16 in an end distal from the box 14 when the vent 10 is assembled. The fingers 16 complement the corrugations in COLORBOND® steel so as to provide a snug connection between the shroud and the roof for adequate weather proofing.

In the case of mounting on material other than COLORBOND® steel, the vent 10 is provided with soldered lead skirts (not shown) for moulding over roof tiles, etc. to provide weather proofing between the vent 10 and wall or roof, for example. Additionally, the fingers 16 would be omitted from such a shroud 12.

A sealing material (not shown) is secured at the underside of the vent 10 to meet standards for buildings in bushfire rated zones by filling the troughs in the corrugations of the roof. The seal comprises non-combustible closed cell material and acts to prevent embers from being blown into the roof space, for example.

The box 14 is provided with holes therein, into which a respective inlet 18 is fitted, preferably being 150mm in diameter. It is preferred that the vent 10 comprises either one, two or four inlets 18. Where the vent 10 comprises one or two inlets 18, it is preferred that a base of the box 14 is approximately 510 mm long, and a top of the shroud 12 is about 360 mm long. Where the vent 10 comprises four inlets 18, it is preferred that the length of those same parts are approximately 710 mm and about 560 mm respectively. Where the vent comprises one inlet 18, it is preferred that a width of those same parts are between about 270 mm and 274 mm. Where the vent comprises two or four inlets 18, it is preferred that those widths are between about 440 mm and 444 mm.

It is preferred that a rear wall 38 of the box 14 is angled as can be seen in FIG. 2. The angle of the rear wall 38 is such that a top of the box 14 is longer than the base. In use, the angled rear wall 38 acts to assist the exhaust to exit the vent 10 away from the structure on which the vent 10 is mounted. In such a way, exhaust is less likely to affect the roof around the vent 10, for example, including staining.

As can be seen, the inlets 18 meet the box 14 at an acute angle thereto. It is preferred that the angle at which the inlet 18 meets the box 14 is between about 20 and 50 degrees and more preferably about 35 degrees. Hence, as would be understood by the skilled person, flow of exhaust past the inlet 18 and into the box 14 would be directed by said angle towards a distal end of the box 14.

A valve 20 is disposed within the vent 10 prior to the outlet 28. The valve 20 is a one-way valve ensuring that, in use, exhaust may pass from inside a building to which the vent 10 is mounted, through the vent 10, to outside the building and is prevented from flowing in an opposite direction into the building. It is preferred that the valve 20 is provided as a forwardly angled flap mounted on a hinge 34, disposed such that, at rest, the valve closes the pathway between the building and the outlet 28 under the force of gravity.

Optionally, the vent 10 may be provided with a divider plate 24 fitted between the shroud 12 and box 14 isolating left and right, and optionally front and back, inlets 18 from one another, on a multiple-inlet 18 vent 10. This divider plate 24, in use, further acts to prevent exhaust from inlet/s 18 on one side of the vent entering inlets 18 on the opposite side. For example, if one inlet 18 (on a two-inlet 18 vent 10 as seen in FIG. 1) receives exhaust from a toilet fan, the likelihood of foul exhaust returning to the building through the opposite inlet 18 is practically eliminated. Where the vent 10 comprises more than one inlet 18, the valve 20 comprises a split 36 to allow the divider plate to be disposed there through and respective valves 20 to operate independently of one another.

As best seen in FIG. 1, the outlet 28, being the open portion of the box 14 not covered by the shroud 12, is fitted with a screen 26, allowing exhaust to be expelled from the vent 10, while preventing particles from entering the vent 10. Preferably, the screen 26 is provided as 2 mm stainless steel cinder mesh. The size of the outlet 28 is optimised to account for restriction of exhaust flow caused by the screen 26. In order to reduce the chance of the metal of the screen 26 from contacting and/or reacting with the metal of the vent 10 and possibly causing corrosion, the screen 26 is isolated from the vent 10 using insulation 32. The insulation 32 is provided at all locations on the vent 10 where the metals are proximal to one another, including sides and ends of the vent 10. Preferably, insulation 32 comprises specialised high voltage electrical adhesive tape, which is also heat resistant (e.g. Kapton®). Otherwise, heat resistant insulation paint may be used. Alternatively, isolation can be effected using nylon strips provided between the screen 26 and vent 10.

As best seen in FIGS. 3 and 4, in connection with the inlets 18 are lengths of ducting 30, typically flexi-duct, as is known. The ducting 30 provides a connection between an extraction fan in a ceiling and the vent 10 through the roof space, for example. Preferably, one 6 m length of quality flexi-duct, tested to 120° C., is provided fitted to each respective inlet 18. Alternatively, an angled spigot (not shown) may be disposed between the inlet 18 and ducting 30. The spigot is appropriately angled (about 35 degrees) such that the ducting 30 is disposed perpendicularly to the base of the vent 10.

In use, the vent 10 is mounted on a building in a preferred location. Firstly, the box 14 is located on a roof, for example, such that the inlets 18 are ideally situated. The divider plate 24 is optionally fitted into the box 14 in the correct place between the inlets 18, usually with the use of blind rivets. Next, the shroud. 12 is placed to cover part of the box 14. In the case of mounting on a COLORBOND® steel roof, the vent 10 is usually blind-riveted to the roof in six places. The fingers 16 are matched to the corrugations in the roof and fixed with screws, then sealed with silicone to prevent rain water from entering the building through the vent 10. In the case of mounting on a tiled roof, for example, the skirts are fixed to the tiles in a manner as would be understood in the art.

The screen 26 is fixed onto the outlet 28 in the vent 10, usually through the use of screws. As mentioned previously, the screen 26 may be isolated from the vent 10 with insulation 32 disposed between the two. The screen 26 over the outlet 28 prevents the ingress, into the building, of vermin, insects, leaves, embers, and many other unwanted materials. Both the screen 26 and the shroud 12 are easily removable from an installed vent 10, thereby allowing for cleaning of those parts and other internal parts of the vent 10.

The lengths of ducting 30 extending from the inlets 18 are connected, at the end thereof distal to the vent 10, to exhaust fans from which extraction is required. For example, in a two-inlet 18 vent 10 such as that of FIG. 1, one length of ducting 30 may be connected to a kitchen rangehood and the other to a toilet exhaust fan. The lengths of ducting 30 may be cut to size or lengthened as required. Accordingly, the vent 10 provides an outlet for two exhaust fans in a building and hence substitutes two mushroom vents, thus providing a cost saving for a builder, etc. The vent 10 also possesses a great aesthetic advantage over mushroom and other previously known vents.

When an internal exhaust fan is operated, exhaust, as shown in FIGS. 3 and 4 as spots, is pulled by the fan into respective ducting 30 and there through to the respective inlet 18. The exhaust then passes through the inlet 18 and into the box 14. The force of exhaust entering the box 14 causes the valve 20 to open by rotating away from the inlet 18 about its hinge 34 and thereby creating an opening between the bottom edge of the valve 20 and the box 14 for the exhaust to escape through (see FIG. 3). Where the vent 10 comprises multiple inlets 18 and optionally the divider plate 20, respective valves 20 are capable of rotating independently of one another. As such, exhaust from one fan is not allowed to enter the other inlet 18 to eventually escape into the other room. Importantly, this means that exhaust from a toilet, for example, will be unable to enter a kitchen, for example, through the kitchen rangehood. As such, merely one vent 10 is required to provide an outlet for both these exhaust fans. The divider plate 24 further reduces the instance of exhaust from one inlet 18 entering the other inlet 18 once the exhaust reaches the vent 10.

Due to the angle of connection of the inlet 18 to the box 14, exhaust is purposefully directed into the box towards the outlet 28. This forced direction of exhaust into the vent 10 through the inlet 18 towards the outlet 28 is advantageous for the ideal direction of the exhaust resulting in significantly reduced friction of the exhaust, thus minimising back pressure and reduction of back-flow of exhaust, as well as less noise from the exhaust fan and/or vent.

Finally, the exhaust exits the vent at the outlet 28 by passing through the screen 26. As would be understood, the exhaust exits the vent 10 in an upwards direction, further assisted by the angle of the rear wall 38, thereby moving away from the roof, compared with a typical mushroom vent, which directs exhaust downwards onto the roof. The vent 10 is capable of tolerating up to 2000 m³ of exhaust per hour, making it an ideal vent 10 for high powered barbecue rangehoods.

It has been advantageously found that the vent 10 of the present invention is suitable for mounting and use upon a wall of a two-storey house, for example, for wall-vented exhaust. The vent 10, and specifically the valve/s 20, also prevent the ingress of undesirable hot or cold air to the building.

Other exhaust roof vents 10 are also contemplated in accordance with the present invention. For instance, one or more solar cells may be fitted to the shroud 12. This may be used to power a motor fitted to an inlet 18 to expel hot air from a roof space. Alternatively, a fan may be utilised to extract hot air from an attic or loft via ducting 30 connected to a ceiling vent. Further, while the vent 10 has been described as having one, two or four inlets 18, optionally with a divider plate 24 between right and left side inlets 18, the vent 10 may comprise an alternative number of inlets 18, for venting of exhaust from a building with a different number of exhaust fans.

Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention. 

What is claimed is:
 1. A vent for venting of exhaust from a building comprising: at least one inlet for receiving the exhaust from the building into the vent; at least one valve for assisting in maintaining the unidirectional movement of exhaust from inside to outside the building; and an outlet for allowing the release of the exhaust from the vent; wherein the inlet meets the vent at a forward angle such that the exhaust flows towards the outlet and acts to reduce friction of the exhaust against the vent.
 2. A vent according to claim 1, wherein the angle at which the inlet meets the vent is between about 20 and 50 degrees.
 3. A vent according to claim 2, wherein the angle at which the inlet meets the vent is about 35 degrees.
 4. A vent according to claim 1, wherein an angled spigot is connected to an entry to the inlet.
 5. A vent according to claim I, wherein a default closed position of the valve is maintained through the force of gravity.
 6. A vent according to claim 1, wherein the vent comprises a plurality of inlets and a divider disposed between the inlets for providing a physical barrier between respective inlets.
 7. A vent according to claim 1, wherein a rear wall of the vent is angled outwardly from a base to a top of the vent.
 8. A vent according to claim 1, wherein the outlet is covered with a screen for allowing exhaust to be expelled from the vent while minimising the ingress of foreign articles to the vent.
 9. A vent according to claim 8, wherein the screen is constructed of cinder mesh for the prevention of ingress of embers in a fire situation.
 10. A vent according to claim 8, further comprising insulation isolating the screen from other material of the vent at points of contact between the two.
 11. A vent according to claim 1, further comprising fingers for complementary attachment of the vent to a corrugated building surface.
 12. A vent according to claim 1, further comprising a malleable skirt for moulding over a surface upon which the vent is mounted.
 13. A vent according to claim 1, wherein a shell of the vent is formed of a box and a shroud.
 14. A vent according to claim 13, wherein the box and the shroud are each formed of a solitary piece punched from sheet material, then folded and fixed into its finished shape.
 15. A method of venting exhaust from a building comprising the use of a vent according to claim
 1. 